Suction device attachment with a suction channel

ABSTRACT

The invention relates to a suction device attachment ( 1 ) comprising a suction channel ( 5 ), whereby a component ( 9 ) whose insertion is to be monitored is disposed in said suction channel. A valve (V) having a movable closing body ( 6 ) in the form of a valve ball ( 7 ) that is freely retained in a valve chamber ( 8 ) is mounted behind the component ( 9 ) in the direction of flow (R). The invention aims at ensuring reliable insertion of such a vacuum cleaner attachment that is disposed in such a way as to protect against jamming, destruction or manipulation and that stops the volumetric suction flow when no component or a wrong component is inserted. To this end, an inlet cross section of the valve chamber ( 8 ), which is reduced by the insertion of the component ( 9 ) to be monitored, provokes a sufficient flow deflection (S) so as to move the valve (V) to the opening position, whereby the cross section of the hole is so large that the valve ball ( 7 ) is pressed into its closing position by the pressure of the flow when the component ( 9 ) is not inserted.

FIELD AND BACKGROUND OF THE INVENTION

The invention relates to a suction-appliance attachment having a suctionchannel, there being disposed in the suction channel a component whichis to be monitored in terms of insertion and downstream of thecomponent, as seen in the flow direction, a valve which has a movableclosure body in the form of a valve ball secured freely in a valvechamber.

Mechanical solutions are known as means for ensuring reliable insertion.For this purpose, use is made, for example, of levers or similarlyactuated elements which, when the necessary components are not inserted,block the functioning of the appliance to a greater or lesser extent. Onaccount of the mechanics, such systems are susceptible to being jammed,destroyed or manipulated. Furthermore, in the case of suction-applianceattachments for the wet-cleaning of surfaces, it is known to provide amovable closure body, for example in the form of a ball, which can betriggered when exposed to moisture. Such an arrangement is known, forexample, from DE-A1 196 54 335. The contents of this laid-openapplication are hereby included in full in the disclosure of the presentinvention, also for the purpose of incorporating features of this patentapplication in claims of the present invention.

SUMMARY OF THE INVENTION

In respect of the above-described prior art, it is an object of theinvention to provide a means for ensuring reliable insertion for asuction-appliance attachment of the type in question which is disposedsuch that it is protected against being jammed, destroyed andmanipulated and which, when a component is not inserted or an incorrectcomponent is inserted, suppresses the suction-volume stream.

This problem is solved first and foremost by the subject matter of claim1, this being based on the fact that an inlet cross-section of the valvechamber, which is reduced in size by insertion of the component which isto be monitored, effects a flow deflection which is sufficient for theopening position of the valve, it being the case that, when thecomponent is not inserted, the opening cross-section is large enough forthe valve ball to be pressed into its closure position by the flowpressure. By virtue of a particular cross-sectional profiling of thesuction channel and/or of the valve ball in the region of the valveformed, the flow around the closure body, when the correct component isinserted, is configured such that the axial forces acting keep theclosure body in a state of equilibrium. These forces are, for example,the weight forces resulting from the dynamic and static pressure andalso the frictional forces as well as, in the case of means according tothe invention for ensuring reliable installation being disposed in asuction-appliance attachment for the wet-cleaning of surfaces, themomentum and/or the impact forces. As is known from the patentapplication mentioned in the introduction, the closure body, in the caseof the normal oncoming flow being superimposed by a mass flow ofincreased density, is displaced, by this additional momentum, into aclosure position from its position of equilibrium, which forms thevalve-opening position. This effect is utilized according to theinvention in order to form the means for ensuring reliable insertion.When a component is not inserted or when an incorrect component isinserted, the flow deflection which is required for the state ofequilibrium in the valve in the open position is thus not provided, sothat the flow pressure to which the closure body is then subjectedpresses this closure body more or less abruptly into the closureposition. The flow deflection which is required for the opening positionof the valve can thus only be set by the correct component beinginserted. As a result of this configuration, with the exception of theclosure body formed as a valve ball, there is no need for any furthermovable parts in order to form the means for ensuring reliableinsertion. Furthermore, the configuration according to the inventionalso gives a high level of protection against manipulation, since theclosure body, formed as a ball, is in a concealed position, inaccessiblefrom the outside. Providing a valve ball further counteracts jamming ofthe closure body. As a further advantage of the means according to theinvention for ensuring reliable insertion, it should be pointed out thatthis means operates without using electrical energy, as a result ofwhich there is no need for any energy converters, such as for examplemotors or electromagnets. It is further found to be advantageous thatthe means according to the invention for ensuring reliable insertion canbe used as often as desired. The configuration according to theinvention ensures interruption of the suction-volume stream when thecomponent is not inserted or an incorrect component is inserted. As aresult, the user of the suction-appliance attachment provided with thismeans for ensuring reliable insertion is obliged to insert the correctcomponent in order to operate the appliance. In the case of being usedin a suction-appliance attachment for the wet-cleaning of surfaces, acomponent which is to be monitored in terms of insertion may be a spongebody for taking up the absorbed cleaning liquid, the insertion of whichsponge body is imperative for maintaining reliability. In a test tooperate the appliance without a system-compatible storage/sponge body,the closure body, formed as a valve ball, is pressed abruptly into theclosure position, in order to interrupt the volume stream, by theincreased flow pressure. It is thus not possible, in this example, forany liquid to be taken in without control. If, in contrast, the correctsponge body is properly inserted, then, by virtue of the flow deflectionprovided here in the region of the inlet cross-section, the closure bodyremains in its position of equilibrium, which defines the openingposition of the valve and which the closure body only leaves when amass-flow threshold value is exceeded, for example once the maximumliquid absorption of the sponge body has been exceeded. Thisconfiguration according to the invention provides positionallyindependent detection of necessary components in minimal installationspace, while simultaneously providing a fluidic switching signal with alarge switching-force range. An advantageous further development of thesubject matter of the invention provides that the inlet cross-section isformed as a perforated base. The openings provided in the perforatedbase are dimensioned and positioned such that, when a correct componentis inserted, a flow deflection which causes the valve to open isprovided in the region of the inlet cross-section. If, in contrast, nocomponent or an incorrect component is inserted, then the air flowingthrough the further openings in the perforated base effects disruptionof the equilibrium-providing flow deflection. Furthermore, it isprovided that the perforated base has a central clearance through whichthe valve ball does not pass. This clearance preferably forms the inletcross-section of the valve chamber, it being further preferred for thechannel cross-section of the valve chamber to be greater than theclearance cross-section. As a result of the fact that, in a furtherpreferred manner, the valve ball has a diameter which is larger than theclearance, an in particular sharp-edged deflection of the volume streamwhich enters into the valve chamber from the clearance, and flows aroundthe valve ball, effects a supporting vortex in the region of the closurebody, so that the latter remains in the position of equilibrium, whichdefines the opening position of the valve. If, in contrast, when thecomponent is not inserted or an incorrect component is inserted, furtheropenings of the perforated base are released, then the air flowing inthrough the further openings disrupts the supporting vortex, so that thevalve ball, entrained by the flow, is pressed into the closure position.Furthermore, it is proposed that the component which is to be monitoredhas a flow clearance adapted to the central clearance. As a result ofthis configuration, there is no disruption to the flow behaviour in theproper state, i.e. when the correct component is inserted, in the regionof the central clearance. It may further be provided that the perforatedbase has symmetrically distributed openings which are disposed, forexample, in a uniformly distributed manner around the central clearanceof the perforated base. When the correct component is inserted, theseopenings are closed by this component, so that the element for ensuringreliable insertion operates satisfactorily. If, in contrast, nocomponent is inserted or an incorrect component is inserted, then themonitoring cross-sections, which are kept open at least partially as aresult, cause the closure body to be displaced into the valve-closureposition. The openings here may be of any desired shape, the overallsize of the opening cross-sections being in the range from 10-50% of theinflow cross-section, i.e. of the cross-section of the clearance. As analternative to the previously described alignment of the openings, itmay also be provided that the perforated base has non-symmetricallydistributed openings. Finally, the configuration here may be selectedsuch that an opening is formed as a circle-segment-like slot whichextends in a region of the perforated base between the central clearanceand the valve-chamber wall. Adaptation of the closure-body weight makesit possible to set the reaction threshold and the reaction time. It isthus possible to use, for example, an HDPE plastics ball having a weightfrom 1 to 10 grams.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is also explained hereinbelow with reference to theattached drawing, although the latter only illustrates two exemplaryembodiments. In the drawing:

FIG. 1 shows a suction-appliance attachment which is connected to avacuum cleaner via a suction tube and is intended for the wet-cleaningof surfaces; FIG. 2 shows, in a schematic illustration, a longitudinalsection through a first embodiment of a valve, the valve being in theopening position with the component which is to be monitored inserted;FIG. 3 shows the section along line III—III in FIG. 2; FIG. 4 shows asectional illustration corresponding to FIG. 2 but with the valve in theclosure position with the component which is to be monitored notinserted; FIG. 5 shows a cross-sectional illustration according to FIG.3, but relating to a second embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A suction-appliance attachment 1, in this case for the wet-cleaning ofsurfaces, will be illustrated and described first of all with referenceto FIG. 1. This suction-appliance attachment 1 is in flow connectionwith a floor-supported vacuum cleaner 3 via a suction tube 2. In thecase of a configuration of the suction-appliance attachment 1 for thewet-cleaning of surfaces, as is known a cleaning liquid is applied tothe surface which is to be cleaned and, at the same time, is extractedby suction together with the particles of dirt which have been taken up.For this purpose, the suction-appliance attachment 1 has a dirty-watertank 4 (not illustrated any more specifically in FIG. 1) in the regionof a suction channel 5 formed in the attachment. The absorbed liquid isdeposited in this tank 4.

Disposed downstream, as seen in the flow direction R, of this tank 4 isa valve V which can be triggered when exposed to moisture duringoperation and, when a predetermined residual moisture content in the airstream is exceeded, closes the suction channel in order to interrupt theair stream.

FIGS. 2 to 4 illustrate a first embodiment of a valve V, which hassubstantially a valve ball 7 forming a closure body 6. This ball isdisposed, such that it can be moved in the axial direction of thesuction channel 5, in a region which is cross-sectionally larger thanthe suction channel 5. This region of enlarged cross-section forms avalve chamber 8.

According to the patent application mentioned in the introduction, towhich you are referred again at this stage as well, it is possible forthe valve chamber 8 to be provided with inwardly projecting ribs, whichare disposed on its inner wall and are aligned in the axial direction ofthis chamber, in order to form a cage. It is also possible to provide,in the region of the valve-inlet opening, a stop pin which can beadjusted in the axial direction and is intended for defining thevalve-opening position.

According to the invention, the valve V serves, at the same time, as anelement for ensuring reliable insertion, in order to monitor theinsertion of a component 9 which, in the exemplary embodimentillustrated, is a sponge body 10 for absorbing liquid. This sponge bodyis a constituent part of the dirty-water tank 4.

In particular in the case of the suction-appliance attachment 1 beingconfigured for the wet-cleaning of surfaces, it is imperative, in orderto operate the appliance, to insert a liquid-absorbing sponge body 10.If the latter is absent, this may, as is known, result in damage, inparticular in the region of the floor-supported vacuum cleaner 3.Furthermore, for reasons of user safety, no liquid must pass into theelectrical regions of the vacuum cleaner.

In order to form the means for ensuring reliable insertion, the inletcross-section of the valve chamber 8 is formed as a perforated base 11which has a central clearance 12 through which the valve ball 7 does notpass. The diameter of the clearance 12 here corresponds approximately tothe diameter of the suction channel 5 in the operating position.

The clearance 12, furthermore, is disposed in axial extension of thesuction channel 5, the valve chamber 8 having a larger diameter than thecentral clearance 12.

Furthermore, the chamber 13, which accommodates the sponge body 10, alsohas a larger diameter than the central clearance 12.

In the annular region remaining between the clearance 12 and thevalve-chamber wall 14, the perforated base 11 is provided withadditional openings 15, four openings of equal size being disposed in auniformly distributed manner in the exemplary embodiment illustrated(see sectional illustration in FIG. 3).

The component 9 which is to be monitored—in this case the sponge body10—has a flow clearance 16, adapted to the central clearance 12, inorder to form the suction channel 5.

In FIG. 2, a component 9 which is to be monitored—in this case a spongebody 10—has been inserted into the chamber 13 in the correct position.The annular end surface 17, which is oriented in the direction of thevalve V, closes the additional openings 15, which are formed in theperforated base 11. As a result, upon operation of the appliance, thevolume stream only enters into the valve chamber 8 by way of theclearance 12, flowing around the closure body 6 (valve ball 7) disposedin the chamber. The rotationally symmetrical closure body 6 here is keptin a state of equilibrium, if appropriate, by the particular profilingof the valve-chamber cross-section, this being brought about by thesharp-edged inlet region to the valve chamber 8 and the supportingvortex S formed in the corner zones 18 as a result.

This state of equilibrium is independent of the flow speeds in the tworegions, this presupposing that the proper component 9, which closes theadditional openings 15 of the perforated base 11, has been inserted.

It is also possible, furthermore, in contrast to the exemplaryembodiment shown, for the component 9 to be some other appliance partwhich is imperative for the operation of the appliance, for example afilter element.

The fluidic means which is formed for ensuring reliable insertion doesnot disrupt the blocking function of the valve V upon insertion in asuction-appliance attachment for wet-cleaning purposes. It is also thecase here, as in the patent application mentioned in the introduction,that, in the case of the normal oncoming flow being superimposed by amass flow of increased density, the valve ball 7 is moved, from theposition of equilibrium according to FIG. 2, into a valve-closureposition, in which the valve ball 7 closes the valve-chamber outlet 19with sealing action, which results in the suction-air stream beinginterrupted.

If, in contrast, according to the illustration in FIG. 4, no component9—in this case sponge body 10—is inserted, then air flows into thecorner regions 18 of the valve chamber 8 by way of the now exposedopenings 15 of the perforated base 11, as a result of which thesupporting vortex S is destroyed and the state of equilibrium is changedsuch that, upon operation of the appliance, i.e. when the suction-airstream is switched on, the valve ball 7 is displaced into the closureposition, in which the suction-air stream is interrupted. Accordingly,the desired suction process cannot be carried out without a properlyinserted component 9.

Furthermore, it is also possible for the means according to theinvention for ensuring reliable insertion to act when the component 9 isnot fully inserted and/or the component 9 is inserted but is notcompatible. The reliability of this system is thus always ensured.

The sectional illustration according to FIG. 5 illustrates analternative configuration of the additional opening 15. The latter is inthe form of a circle-segment-like slot 20 in this case, it also beingthe case here, as in the previously described exemplary embodiment, thatthe opening cross-section corresponds approximately to 0.1 to 0.5 timesthe clearance cross-section.

We claim:
 1. Suction-appliance attachment (1) having a suction channel(5), there being disposed in the suction channel (5) a component (9)which is to be monitored in terms of insertion and downstream of thecomponent (9), as seen in flow direction (R), a valve (V) which has amovable closure body (6) in form of a valve ball (7) secured freely in avalve chamber (8), an inlet cross-section of the valve chamber (8),which is reduced in size by insertion of the component (9) which is tobe monitored, effects a flow deflection (S) which is sufficient foropening position of the valve (V), wherein, when the component (9) isnot inserted, opening cross-section is large enough for the valve ball(7) to be pressed into its closure position by flow pressure. 2.Suction-appliance attachment according to claim 1, wherein the inletcross-section is formed as a perforated base (11).
 3. Suction-applianceattachment according to claim 2, wherein the perforated base (11) has acentral clearance (12) through which the valve ball (7) does not pass.4. Suction-appliance attachment according to claim 3, wherein thecomponent (9) which is to be monitored has a flow clearance (16) adaptedto the central clearance (12).
 5. Suction-appliance attachment accordingto claim 2, wherein the perforated base (11) has symmetricallydistributed openings (15).
 6. Suction-appliance attachment according toclaim 2, wherein the perforated base (11) has non-symmetricallydistributed openings (15).
 7. Suction-appliance attachment according toclaim 1, wherein an opening (15) is formed as a circle-segment-like slot(20).